The address lookups from ADB were not being validated, allowing spoofed responses to be accepted and used for other lookups. Validate the answers except when CD=1 is set in the triggering request. Separate ADB names looked up with CD=1 from those without CD=1, to prevent the use of unvalidated answers in the normal lookup case (CD=0). Set the TTL on unvalidated (pending) responses to ADB_CACHE_MINIMUM when adding them to the ADB.